fix(discovery): correct subagent directory path structure

Subagents live at <session-uuid>/subagents/ (a sibling directory to
the session JSONL), not at <project-dir>/subagents/. Fix both
discover_agents_for_session and discover_all_agents to use the correct
path, and update integration tests accordingly.

Closes claudbg-33n0

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.beans/claudbg-33n0--agent-discovery-looks-in-wrong-subagents-directory.md

@@ -1,11 +1,11 @@
 ---
 # claudbg-33n0
 title: Agent discovery looks in wrong subagents directory — sessions show 0 agents
-status: todo
+status: completed
 type: bug
 priority: high
 created_at: 2026-03-30T04:43:21Z
-updated_at: 2026-03-30T04:43:21Z
+updated_at: 2026-03-30T05:01:30Z
 ---
 
 ## Problem
@@ -61,3 +61,9 @@ The existing unit tests in `src/commands/agents.rs` (`dump_with_real_agent_retur
 
 - `src/parser/discovery.rs` — `discover_agents_for_session` (lines 198–205), `discover_all_agents` (lines 211–266), `collect_agents_in_dir`
 - `src/commands/agents.rs` — integration tests
+
+## Summary of Changes
+
+- Fixed  in  to use  to derive the sibling  directory
+- Fixed  to iterate UUID subdirectories inside each project dir and call  on each 
+- Updated tests in  (, ) to create agent files at the correct path structure

src/commands/agents.rs

@@ -529,10 +529,12 @@ mod tests {
             .join(".claude")
             .join("projects")
             .join("myproject");
-        let subagents = projects.join("subagents");
-        std::fs::create_dir_all(&subagents).unwrap();
 
         let session_id = "bbbbcccc-dddd-eeee-ffff-000000000000";
+        // subagents live inside a directory named after the session UUID
+        let subagents = projects.join(session_id).join("subagents");
+        std::fs::create_dir_all(&subagents).unwrap();
+
         let session_file = projects.join(format!("{session_id}.jsonl"));
         std::fs::write(
             &session_file,
@@ -566,10 +568,12 @@ mod tests {
             .join(".claude")
             .join("projects")
             .join("myproject");
-        let subagents = projects.join("subagents");
-        std::fs::create_dir_all(&subagents).unwrap();
 
         let session_id = "ccccdddd-eeee-ffff-0000-111122223333";
+        // subagents live inside a directory named after the session UUID
+        let subagents = projects.join(session_id).join("subagents");
+        std::fs::create_dir_all(&subagents).unwrap();
+
         let session_file = projects.join(format!("{session_id}.jsonl"));
         std::fs::write(
             &session_file,

src/parser/discovery.rs

@@ -193,14 +193,26 @@ pub fn discover_sessions() -> crate::error::Result<Vec<SessionRef>> {
 
 /// Discover all sub-agent runs for a session given the session's JSONL file path.
 ///
-/// Looks for `subagents/agent-*.jsonl` files in the same directory as
+/// The actual disk layout is:
-/// `session_file`.
+/// ```text
+/// <project-dir>/
+///   <session-uuid>.jsonl
+///   <session-uuid>/          ← directory named after the UUID (no extension)
+///     subagents/
+///       agent-<id>.jsonl
+/// ```
+/// So we derive the sibling directory from the file stem and look inside it.
 pub fn discover_agents_for_session(session_file: &Path) -> crate::error::Result<Vec<AgentRef>> {
     let parent = match session_file.parent() {
         Some(p) => p,
         None => return Ok(vec![]),
     };
-    let subagents_dir = parent.join("subagents");
+    let stem = match session_file.file_stem() {
+        Some(s) => s,
+        None => return Ok(vec![]),
+    };
+    let session_dir = parent.join(stem);
+    let subagents_dir = session_dir.join("subagents");
     collect_agents_in_dir(&subagents_dir, None)
 }
 
@@ -249,7 +261,35 @@ pub fn discover_all_agents() -> crate::error::Result<Vec<AgentRef>> {
             continue;
         }
 
-        let subagents_dir = proj_path.join("subagents");
+        // Each project dir may contain zero or more <session-uuid>/ subdirectories.
+        // Each of those may have a `subagents/` directory inside it.
+        let session_dir_entries = match std::fs::read_dir(&proj_path) {
+            Ok(e) => e,
+            Err(err) => {
+                eprintln!(
+                    "claudbg: could not read {}: {}",
+                    proj_path.display(),
+                    err
+                );
+                continue;
+            }
+        };
+
+        for session_dir_entry in session_dir_entries {
+            let session_dir_entry = match session_dir_entry {
+                Ok(e) => e,
+                Err(err) => {
+                    eprintln!("claudbg: error reading session dir entry: {err}");
+                    continue;
+                }
+            };
+
+            let session_dir_path = session_dir_entry.path();
+            if !session_dir_path.is_dir() {
+                continue;
+            }
+
+            let subagents_dir = session_dir_path.join("subagents");
             match collect_agents_in_dir(&subagents_dir, None) {
                 Ok(mut found) => agents.append(&mut found),
                 Err(err) => {
@@ -261,6 +301,7 @@ pub fn discover_all_agents() -> crate::error::Result<Vec<AgentRef>> {
                 }
             }
         }
+    }
 
     Ok(agents)
 }